Article Type

Original Study


Objective The aim of this study was to evaluate the efficacy and safety of ultraviolet A irradiation cross-linking on completion of laser-assisted in-situ keratomileusis (LASIK) in risky patients to avoid post-LASIK ectasia. Background Patients with thinner-than-normal corneas, irregular corneal astigmatism, asymmetry on corneal topography, against-the-rule astigmatism, or steeper-than-normal corneas have higher risk of development of post-LASIK ectasia which need improvement in surgical interference. Materials and methods Forty-eight eyes of 30 myopic patients presented for LASIK at Al-Fardous Eye and Dental Hospital, Zagazig, Egypt, between September 2013 and August 2014. The study group comprised risky patients with corneal thickness of at least 480 μm and postoperative residual stromal thickness of at least 300 μm. After reflecting the flap, 0.1% riboflavin sodium phosphate solution was applied on the bare stromal bed and left to be soaked in for 60 s, and then the patient was positioned with the ultraviolet light (typically 365-370 μm). Results The study proved that there was an improvement in mean spherical error from −4.05 ± 1.19 preoperatively to −0.98 ± 0.12 on the second day postoperatively, and it improved to −0.59 ± 0.49, −0.49 ± 0.39, and −0.39 ± 0.36 at 1, 3, and 6 months postoperatively, respectively. These results showed a statistically highly significant difference (P < 0.001). Visual acuity improved from 0.828 ± 0.33 best-corrected visual acuity preoperatively to 0.881 ± 0.11, 0.894 ± 0.21, 0.9 ± 0.22, and 0.913 ± 0.22 at second day postoperatively, and 1, 3, and 6 months postoperatively, respectively. However, the improvement did not show a statistically significant difference (P > 0.05) because we compared the results with the preoperative best-corrected visual acuity. Conclusion Application of riboflavin with ultraviolet after LASIK in risky patients improves refractive errors (spherical and cylindrical errors) and prevents post-LASIK corneal ectasia.